1. Field of the Invention
The present invention relates generally to machines used in the nursery industry for extracting seedlings from a plug tray and transplanting them into yet another growing tray having a greater area of separation between seedlings than the plug tray in order to encourage continued growth of each individual seedling.
2. Description of the Related Art
In the nursery industry, plants are initially grown in arrays of small compartments within plastic trays. The small compartment size fully accommodates the plant in the early stages of its development while economically making use of the limited space available within a greenhouse or other nursery building. Once the seedlings have germinated and have approached the maximum size desirable in the small germination compartments, each seedling must be transplanted to a larger pot for further growth and eventual outdoor planting or commercial sale.
The roots of the seedlings will typically form a compact ball with the soil contained within the germination compartments, which allows the seedling and the associated soil to be transplanted as a unit (the seedling "plug"). Typically, seedlings have been transplanted by hand into pots prefilled with soil. Hand transplanting allows seedlings to be easily transplanted from seedling arrays of any configuration to single pots or, more commonly, arrays of pots contained within a unitizing flat. However, the high cost of labor and the seasonal nature of transplanting work has made this method undesirable.
Automatic transplanters are known which utilize specially fabricated seedling flats which permit the seedlings to be pressed through the base of a germination compartment into a pot located below. Other known transplanters use cam-driven rotating pairs of plate-like fingers to extract the seedlings, or utilize prebent metallic wire fingers which are retained in a straight configuration and injected into the soil surrounding the seedling. It is known to move the germinating tray on an indexable table with respect to the transplanting head of the apparatus.
What is needed is an apparatus of sturdy construction which may readily accommodate germinating trays of varying array dimensions, and which will rapidly transplant seedlings to pot arrays of a desired configuration. The present invention relates to apparatuses and methods of transplanting young plants from seedling trays to larger trays.
In the art to which the invention relates, complicated systems have been developed to transplant plants from a seedling plug tray, where they have initially germinated, to a larger flat tray where they will have more room to grow. These systems have been unduly complicated, and have sometimes injured the seedlings. For example, a begonia seedling has broad leaves that grow close to the surface of the soil from which the stem extends. These prior systems and machines have been known to damage the begonia leaves when the seedling is extracted from the tray in which it germinates originally. These systems have also not been able to rapidly transplant the large number of seedlings of any variety in a typical seedling tray.
Further, the art to which the invention relates has not been easily adaptable for use with varying trays and plants. Also, in the prior art, pointed members have often been used to force the seedlings out of the seedling tray compartments.
It would be desirable to develop a plant transplant apparatus and method which can quickly and accurately transplant plants from a seedling tray to a larger tray. Further, it would be desirable to develop such an apparatus and method which can transplant the plants without damaging the seedlings, and have it adaptable to various sizes and types of trays and plants.